Square sine wave converter

And perhaps add some offset voltage for the signal to fit the input voltage range of the op-amp? I would like to suggest that the comparator circuit shown by hwengmgr could use some small improvements over what was posted.

This was simulated with LT-Spice. I used a model for a comparator that was built into the package library. You can substitute a comparator of choice as long as it is specified for operation at a Vdd of 3. If this is a problem it can be easily flipped with a logic element. If you select a dual comparator the other half of the package could be used to invert the signal. If its a continuous waveform, you can use a DC blocking capacitor and then use some resistors to set the DC common mode point and scale it as well.

Then feed it into an LM comparator to get your digital output. Something like this. I have NOT calculated the resistor ratio's! But setting R3 will let you attenuate the incoming waveform. R6 is needed because the LM is open collector output. The gate should have a Schmidt trigger, and support any intermediate voltage at its input, for example an HC The 74HC14 is a digital inverter with schmitt input.

This would then need to interface to 3v3 logic. One thing you don't mention is whether the square wave needs to be square even if the sine wave may be distorted. A simple way to achieve a reasonable result would be:. If given a distorted wave, however in "build" mode, click "SW1" and click "properties" to switch its state the output may not be quite square.

The voltage divider for the comparator's reference voltage may be set to any convenient value; the duty cycle of the input is controlled by the symmetry of the input, rather than resistance ratios; designs to yield a symmetrical output when given a distorted input would have a duty cycle set by a resistance ratio.

Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Can I use a converter shown in your blog anyone from your blog for 12v to 15v?

Is it safe I'm positive towards this regard, please read full and reply soon. Hi Aabhishek, to control high voltage you can add the following circuit to your inverter and see if it helps. Hi sir, could you please help me with some other idea with this matter. Read older comments for revising summary of problem. Please let me know if you have any help for me. Hi sir??? Earlier this problem was not there why is it happening even without pwm, and also with pwm.

This problem happened only today, please tell me what is wrong now. I'm littrally very stressed? Sorry sir, I'm commenting again here but sir firstly I tested it without pwm then I tested the same transformer with my another square wave inverter then output was v.

And I think this setup have damaged both of my transformer as I tested old 5amp transformer 12v then also the output was v, because earlier I had tried both of my transformer with this setup using pwm also and I think my both transformer are now damaged due to this full set may be high frequency done this damage please help, and can we have a video call so I can make you understand more easily.

Hi sir, I'm now double stressed, I, this time recently checked only the square wave part of circuit with my old 5amp transformer and this time I got v even without pwm, I really think that the circuit and pwm have damaged both of transformer now what to do?

This time life sucks?. Sir please help me to convey the details regarding the conversion of 12 volt 50 hz square wave signal to 12 volt 50 hz sinusoidal wave…pls help me in the designing part ,. I know that when using only n channel mosfet for full bridge inverter the mosfets on the high side must be higher than the voltage applied to the drain.

How can that be achieved? Can I parallel them for more power instead of using one set of mosfet for switching? Can you please give me a link to a circuit of any filter that you believe will work perfect or even a complete Sine wave circuit. Hi Sodiq, the RC filter shown in the last circuit is a square wave to triangle wave converter, and it is a proven design, and therefore it has to work.

Please check the RC stage separately using different frequencies and try adjusting the RC part values by some trial and error until you get the desired triangle waveform. Sir I am Nataneil a new person on your site. I am seeking help to build a 24v input fullbridge inverter. I have only irfz46n n channel mosfets for the high side and low side, a cd ice, lm timer ice. I need to know how do I increase the voltage for the high side and to how much voltage.

Hi Nataneil, you can increase the voltage by configuring the IC output with a voltage doubler stage…. Sir I hv some questions- 1. I want to make for oscillator, with Hz and then can integrate PWM with it as like as u shown the 2nd circuit, is it possible? Mehedi, yes It is possible, a few of my other designs have already used the same principle which you are referring to.

Hello sir, i asked some questions in one of ur post and i see no reply, let me ask u the same questions here: 1. Can i use stabilizer transformer to connect with my inverter circuit? Thank you Sir. The issue is that am using a stabilizer container to cover the inverter…thus it wount contain upto 24 12pairs of IRFPN because the Vero Board will be too long.

Hi Steve, no need of ding 12 pairs of mosfets, if you use 24V as the supply, just 3 mosfets on each channel will be enough.. A lot of stuff here, it is very good! I know that the Square Waveform inverter needs a classical iron 50hz transformer to work.

I have a dumb question.. I love your professional sincererity and openness which is the key to personal knowledge development for all humanity. You share openly to the entire universe what costed you sweats to achieve. All of us in the electronic field will forever shower gratitude to a great gem like you. Parts will be the same, but the C1, C2 may need some change until the right frequency is achieved. Thank you sir for the spwm description. Now if i put the upper astable at 50hz,what will be the freq of the lower astable,50hz?.

How can i attach a feedback loop to the circuit. Hi Patrick The lower astable must be 4 times more frequency than the upper astable, feedback loop can be attached using this concept:. Dear Swagatam, Question-1 I found that my 12 volt single battery UPS system using a transformer which secondary coil is volt. Then I open my 24 volt two battery UPS system and I found here using a transformer which is volt secondary coil.

I am confused about this matter because normally we found 12 volt inverter system using volt secondary coil transformer and if it is 24 volt system then using volt transformer. It seems to me I have also change the circuit board some parts but where I change I do not know.

If the inverter is PWM controlled or a SPWM controlled, then the transformer primary value will be normally much lower than the battery voltage. But for a flat square wave design the two values can be similar. Answering the second question can be difficult without checking the entire working specification of the design.

Thanks very much for your quick reply. Normally we know that computer UPS can backup for small time like minute. My question is here any other arrangement needed or not in circuit board for long backup? To increase back up you can add more number batteries in parallel, but the load must not increase. Also the additional batteries will need to be charged from an external charger.

Any other changes will not be required. Dear Swagatam, How are you? After a long time come back to you. My UPS output voltage is volt volt transformer primary coil is connected for output voltage. Frequency is 50 Hz.

But problem is when I connect load like one table fan then output voltage decrease to volt. If I connect more load then decrease the output voltage more. My UPS specification is- 1. UPS input voltage is 12 volt DC. Question-1 Now how can solve this problem or how can increase my UPS watt or output voltage? It is or or Dear Md, the transformer voltage rating will depend on the oscillator circuit specifications…Depending on the PWM duty cycle of the oscillator, the transformer voltage rating could anywhere between V and V, but it cannot be V or higher with a 12V battery.

Sir, do you know much about Fuelless Generator? To generate a steady electricity with a 12V DC motor and a permanent magnet alternator with a feedback charging system to the 12V battery. How PWM voltage works in inverter? If my main transformer primary voltage is then how much PWM voltage needed?

Can I take PWM voltage in seperate transformer instead of main transformer? Can I connect seperate auto charging circuit in my home UPS? Please describe in details. How this type of inverter works without PWM voltage? Dear Zahirul, your questions cannot be explained in comments, you will have to learn the whole concept of MOSFET switching and PWM switching from the beginning, to grasp the whole working.

Hi Zahirul, You will have to wind the high voltage winding first, and then apply the low voltage winding after a layer of insulation tape. Sir swagatam,can the above spwm circuit power heavy loads like a refrigerator,tube lights and induction motors? Can I use it to construct a w inverter, please advise. Hello, square-wave can use transistor for the output stage, modify-square-wave can also use transistor too for the output stage, how about pure sine wave? You can modify a square wave inverter by driving the square wave oscillator with a sine wave IC oscillation driver or by modifying the output of the square wave inverter with a J V Cap to the output transformer.

Hello sir , Thank you so much, In the above diagram,the two diodes appear to be blocking the signal from the lm What do you think?. Hello Patrick, the op amp is used for sinking current not for sourcing current…. I have couple of squarewave inverters replaced with Luminous UPS. Hey there. However the ac output is modified sine, which I have read will damage appliances. Can I use this circuit to covert to sine wave?

Hi, yes definitely you can use the above concept. Hi, which one do I use as best modified sine wave inverter in my shop? The first in the seven modified sine wave inverter or this down one in this post? Thank u sir u r my teacher, I will try ths next week. I have a ups transformer with a battery 32ah. Hope am gona get ac output. Yes my lecturer,Swagatam! How are you? Can I use ths circuit now with or transformer adding a 12v regulator to feed the oscillator?

Thanks in advance! How r u? I have two 12ah lead acid battery which I want to use with this circuit u referred to me as best in my workshop. My question is that can I replace the transistors with mosfet in that Same connection?

Two, is it possible using a transformer with the two batteries to get 24 volts and work efficiently? Just make sure to add diodes between center tap and the outer terminals of the transformer to safeguard the mosfets from damage.

So if I want to use irfan44 four pieces, I jst connect them the same way the four TIP transistors are connected? Yes sir, do u have any best modified sine wave inverter charger for 24v to use in my shop so that whn the main is available it charges the battery and whn the power goes off inverter picks on in the absence of the main?

Pliz guide! The second schematic from the following article is probably the bets and the easiest design you can get. The sine wave has nothing to do with the charger…. And which type of mosfet do u recommend sir for that efficient charging! Irf or which one? Pls what home made simple circuit can i add to my inverter to make it a sine wave strong enough to pick my electronics.

Your email address will not be published. Notify me via e-mail if anyone answers my comment. You'll also like: 1. I need a pure sine wave oscillator to drive my midget power stage of my inverter.

Helo Sadi, Yes you can employ the concept for modifying your existing square wave inverter. Adjust them carefully to get the required results. Dear Sir, I don't understand how to change the position of VR1. Thnx Paul. Dear Paul D1, D2 are connected the gates of the mosfets. And I have a v. Is it ok? Good day! Hello swagatam, if I power only the timer with 5v, will it have an adverse effect on the PWM? The pwm peak voltage should match the gate voltage, that's the only criterion…. Hi Swagatam Can i connect the chopper circuit only to a ready made modified sine wave inverter?

Try incorporating a the following network directly across the output of the inverter 4. Ok then ill try that… I have a clap meter… I could use that instead. Hi Mhmad, yes it can be definitely tried and it should work as proposed. Instead of irf It will work, but a v is not an appropriate match… preferably the voltage rating should be below V and the current above 30 amp.

Hi hisham, use the second circuit and connect the diode ends with the mosfet gates and check the response by adjusting the pot…. Hello Moen, yes it can be applied to any square wave inverter. Hi Moen, please check out the following link: postimg. Thank you Swagatam, The new link works perfectly. I'll try to design it in an easier alternative way and publish it soon.

Regards Bernard Tendengu. My question here is; 1. Thank You very much for your Kind and Helpfull post. I like you very much. Thanks Aminu, I am glad you could make the first circuit successfully.

Thank you once again Sir. I like you very much! That's great Aminu, I am glad to hear this. Thank you very much for your help. May God see you through! Again, I need your help on the above circuit.

Thanks once again Sir, I realy like you much. That's great Aminu, thanks for updating the info. Thank you for all your help to us, and may god bless you and protect you. Pls, help me sir. Thank you very much sir. And I tried it without load as you suggested but the problem is remained unchange But, it worked by the time i build the circuit.

This problem was started when I loaded a laptop. Sir, I have discovered the problem. I learnt that, I placed the VR wrongly that is why Iam facing the problem. Thank you Sir! I discovered again, I included two 27k instead of for 1k at PWM. Thanks, for the help Sir.

Sir, can this procedure work? I also have multimeter but, I think I lack knowledge on how to use it properly. So, I want, if available, any component to make changes. Thank you Sir for all your help. You are great Sir, Thank you very much… And I will do as you mentioned. May God help you, protect you and reward you. Thank you Sir for your time and help. Thank you very much Sir.

I will try this updated version too. I want you to help me as usual with a trick on how to test the following stage. Thank you very much Sir, Iam very proud of you. Hi Aminu, first check the circuit without the lower PWM stage assuming your 50Hz upper inverter works normally, and it should.

Sir, You are great!!! Iam very grateful Sir, Thank for the helps. Ok, Thank you Sir, I will give it try and update you with the result soon. Good Morning Sir, Am back with the result. Sir can you please suggest me what is wrong? Thank you sir. Aminu, The PCB is getting hot because the tracks or the jumpers are not able to bear the higher current level, you should use thicker wires and tracks for the PCB, and use a big heatsink for the mosfets.

Morning Sir, The problem of component borning has been solved by following this procedure. I think, this can save all the components in the board. Sir, still Iam exeriencing some problems. As usual, I need your help Sir to solve them thank you very much sir. Sir, still Iam exeriencing some problems that i dont know their source.

Aminu, remove the PWM feed from the lower circuit, and check the response. I used 12v 20AH battery. Sir, The inverter has no any other problem now because I discovered them and solved them today. Thank you Sir for the help. Thank very much, its few staps remain to build a very reliable low cost inverter.

Aminu, PWM will reduce the RMS of the output voltage therefore the transformer's primary rating should be lower than the battery voltage, V is a good trafo but its current should be at least 10amps, and for higher loads the battery AH should be at least 10 to 20AH fully charged.

Ok Sir, I will try it and update you with the result as soon as possible. Thank for the help Sir. But I load only 26watts economy ligh bulb. Ops, Iam wrong Sir. Sir, I did it. I used this ic configuration, as you suggested me alias. Anyway, Sir, Your help is always appreciated and Iam very much proud of you Sir.

Thank you once again. Aminu, an UPS also has a built-in inverter so that's a wrong assumption. Sir can we convert v square in to v sine wave directly please help me out.

It would be greatly appreciated for any help you could offer…thank you in advance Mad Scientist. Diode 46 discharges both shunt capacitors qickly whenever the signal disappears. Foroward converter 21 has an amplification factor which is determined by the magnitude o feedback resistor 47 connected between the output of amplifier 50 and the inverting terminal of amplifier The DC control signal obtained from this circuit is coupled via resistor 22 to the base electodes of the pair of transistors 32 and 35 in the AGC circuit In the case of converter 23, this feedback resistor has a value such that the gain of this circuit is 2.

Backward converter 3, on the other hand, acts in a closed loop which, as is well known, is a superior mode of controol. Thus, both loops do not share equally in the control of the automatic gain control circuit Differentiating circuit 17, which is responsible for the nonlinearly decreasing DC control voltage characteristic mentioned hereinbefore, is included in the forward loop because the amplitude of the signal at the output of the integrator increases as the frequency of the square wave is decreased.

With the differentiator present, this loop's effectiveness at low frequencies is diminished. The automatic gain control circuit 13 includes an input transistor 30 having a pair of transistors 31 and 32 in its collector circuit. The output of integrator 12 is coupled to the base electrode of transistor A similar series arrangment of transistors 34, 35 and 36 is also connected across the supply voltage terminals, and the signals appearing across load resistors 33 and 37 are fed to an operational amplifier The output of this amplifier is fed to amplifier 14 and back to a second operational amplifier 39 whose output in turn is applied to the base electrode of transistor In the automatic gain control circuit 13, transistors 30 and 37 perform as current sources that are modulated by the input signal.

Their collector currents are steered through transistors 31 and 36 to the load resistors 33 and 37 or through transistors 32 or 35, bypassing these resistors, depending on the voltage conditions at their base electrodes. With less DC control voltage applied to circuit 13, less attenuation is present in the signal processing circuit between integrator 12 and amplifier 14 and, consequently, a signal of increased amplitude appears at the input of driver 15 and at sine wave shaper In this way, the input to shaper 16 is maintained constant despite fluctuations or variations in signal level at the output of integrator What is claimed is: 1.

A wave shaping circuit, comprising in combination: a source of square waves of variable frequency;. A square wave to sine wave shaping circuit, comprising in combination a source of square waves of variable frequency;. A square wave to sine wave shaping circuit which produces a sine wave having a high degree of purity and a constant amplitude, comprising in combination a source of square waves of variable frequency;.

A wave shaping circuit comprising, in combination: a source of square waves of variable frequency;. A swuare wave to sine wave shaping circuit, comprising in combination a source of square waves of variable frequency;. USA en.